Medical Testing for Children with Autism

About this episode

In this episode, I'm walking you through the essential medical tests that every parent of an autistic child should know about, and more importantly, how to decide which ones actually matter for your child. I cover five key areas of testing in autism: genetics, metabolic and nutritional health, brain function, gut health, and the immune system. For each one, I break down what the research says, what's clinically recommended, and how to think about whether it applies to your child.

We start with genetic testing, including chromosomal microarray and fragile X, the two tests that the American Academy of Pediatrics recommends as standard for every child diagnosed with autism, and I explain why genetic testing is not about blame or labeling but about understanding your child's biology.

I walk through metabolic and nutritional screening, including why mitochondrial dysfunction, which some estimates suggest may affect a third or more of autistic individuals, deserves attention, and why common nutrient deficiencies like iron, vitamin D, and B12 can quietly affect learning, mood, and energy in ways that are easy to miss.

I cover EEG and brain function, including how absence seizures can look like daydreaming and go undetected for years. I explain why gastrointestinal symptoms in autism are massively underdiagnosed, and how a child in chronic gut pain may not be able to tell you about it, showing it instead through irritability, aggression, or disrupted sleep.

And I take you into the emerging science of immune involvement in autism, from maternal immune activation to neuroinflammation to folate receptor autoantibodies, a specific and testable mechanism where treatment with leucovorin has shown real promise.

This episode is for you if: you've been told your child "has autism" but no one has walked you through the medical workup, you're unsure which tests are worth doing and which are noise, your child has symptoms like low energy, sleep problems, GI issues, or behavioral changes that no one has fully investigated, or you want a clear, science-backed framework for making informed decisions with your care team.

Throughout, I want you to remember: medical testing on its own is not the goal. Understanding your child is the goal. Supporting their biology is the goal. Creating the conditions where they can feel well, learn, connect, and grow. That is the goal.

Transcript

Click a time to play the video from that point. This transcript comes from the episode’s captions and may contain small errors.

Welcome to Magnificent Minds, where we explore the science of child development with both heart and reason, bringing clarity, compassion and scientific evidence to questions that matter deeply to families. I am so glad you're here today, because I'm going to answer some of the most important questions that every parent of an autistic child should be asking. What are the medical tests that matter for autism and how do I get them for my child? I know from having worked with thousands of families that exploring the biological side of autism can sometimes feel confusing or overwhelming.

There's genetic testing. There are metabolic labs, there's EEG, there's gut testing, immune markers, nutritional panels, and more. There are some doctors who will do every test for every child, and some doctors who don't think there's a role for it. But from my perspective, both of these extremes are wrong. The goal is not to do everything, and it's certainly not to do nothing. The goal is to do what matters for your specific child at the right time and for the right reasons. And today I'll tell you how to do just that.

How to develop a plan based on the best research evidence and what you know about your child, so you can be both thoughtful and efficient so we can cut through the noise. Focus on what actually changes. Care and spend our energy on what genuinely helps your child thrive. Today, I'm going to walk you through five key areas of medical testing in autism, genetics, metabolic health, brain function, gut health, and the immune system. For each one, I'll tell you what the research says. What clinically is recommended, and how to think about whether it applies to your child.

Let's start at the beginning. The first area and the best place to begin is genetics. Now, I know the word genetics can feel a little clinical or maybe even a little scary. Like we're looking for something wrong and potentially something you passed on to your child. So I want to reframe that right from the beginning. Genetics is not about labeling your child. It's not about blame. It's about understanding their biology. And that distinction matters a lot. Here's a useful way to think about it. Imagine different children who present with similar challenges.

Maybe delayed language, sensory sensitivities, difficulty with transitions from the outside. They might look like they have very similar profiles, but on the inside, at the biological level, the reasons for those challenges might be completely different. One child might have, for example, a tiny deletion on chromosome 15. Another might have a change in a gene involved in how brain cells form connections. A third child might have no identifiable genetic finding at all because of their different underlying genetics.

They have different biology. And each of those children may need something different. And genetic testing is one of the most important ways for us to understand what's happening under the surface biologically. So what does the research tell us? Over the past decade, genetics has become one of the most transformative areas of autism science. Large scale studies, including work from the Simons Foundation SPARK cohort, which has enrolled over 50,000 families, have shown us that autism is highly heterogeneous.

What that means is there isn't one autism. There isn't one autism gene. There are hundreds of genes that, if altered, can influence brain development in ways that may lead to the traits we recognize as autism. Some of those genetic differences are inherited from parents, but others arise newly. Those are called a de novo variance, meaning they're present in the child, but not in either parent. And some involve not just individual genes, but maybe larger structural changes in chromosomes, like extra pieces, missing pieces, or rearrangements.

The American Academy of Pediatrics and the American College of Medical Genetics both recommend that genetic evaluation be part of the standard workup for any child diagnosed with autism. Specifically, two tests are considered first line. The first is chromosomal microarray, or sometimes called CMA. This test looks across the entire genome for deletions or duplications of chromosomal material that might not be visible on some of the older standard chromosome tests.

It's more sensitive than what we had even 15 years ago, and it can identify clinically significant findings in about 15% of children with autism. The second test is fragile X testing. Now, fragile X syndrome is the most common inherited cause of intellectual disability and is associated with autism in a meaningful number of individuals, particularly in boys. It's caused by a specific change in a gene on the X chromosome. And together these two tests, chromosomal microarray and fragile X, are the recommended standard.

I'm starting point. But keep in mind the field is moving quickly and even further with genetic testing. So whole exome sequencing, a test which looks at the protein coding portions of all your genes at once, is now being used more widely when the first line tests are unraveling. Now, all these tests can be ordered by a doctor and done using a sample collected from a cheek swab, and just by rubbing a cotton swab on the inside of the cheek. Or they can be done on a blood sample.

And here's why these tests matter. Practically speaking. Finding a genetic answer doesn't just satisfy curiosity. It can actually guide care in really important ways. Some genetic conditions associated with autism carry specific medical, sort of co-occurring conditions or factors. So things like cardiac or heart issues, things like seizures or what's called epilepsy, metabolic vulnerabilities. And these are all things that a doctor needs to know about and to monitor.

In some cases, knowing the underlying genetic mechanism opens the door to the very targeted therapies. It connects families to specific communities of people who share the same diagnosis. It can connect you to new, cutting edge research, trials and therapies, and it provides clarity that many families describe as deeply meaningful. Not so much because it changes who their child is, but because it gives them a more complete picture of their child's biology and their overall health. So if your child has not yet had a genetic evaluation, that's the first conversation to have with your doctor.

It's not a step you need to worry about. It's a step worth taking. The second area I want to cover is metabolic and nutritional health. Let's start with a basic biological fact. The brain is one of the most energy demanding organs in the human body. It uses roughly 20% of your total energy supply, even though it's only about 2% of your body weight. That's remarkable. And it means that the brain is incredibly sensitive to how well the body is running its metabolic machinery.

Now, research in autism has consistently shown that some children have differences in metabolic function. The biochemical processes that generate energy and keep cells running efficiently. Mitochondria, the little organelles inside our cells that produce energy, have been a particular focus. Studies have found that mitochondrial dysfunction is more prevalent in autism than in the general population, with some estimates suggesting it may affect a third of autistic individuals or even more.

Now, when mitochondria aren't working optimally, it can show up as difficulty with learning and memory, slower cognitive processing, mood instability, and lots of other ways. There's also a well-documented relationship between autism and certain nutrient deficiencies. This isn't a fringe observation. It's been replicated across multiple research studies and across many countries. So, in particular, children with autism are more likely to have lower levels of vitamin D, iron, and vitamin B12.

Some of this is related to selective eating. Many autistic children have significant sensory sensitivities around food textures and flavors, which can narrow their diet in ways that affect nutritional intake. Some of it may also reflect differences in how the body absorbs and uses certain nutrients. Addressing these can meaningfully affect a child's ability to engage in school and therapy, to learn new skills, and to demonstrate what skills they do have. It can also affect energy levels, attention, sleep quality, emotional regulation, and so much more.

Think of it this way if a child is low in iron, they may be quietly fatigued in a way that makes learning harder and frustration come faster. If vitamin D is low and remember, vitamin D is not just a bone vitamin. It plays a role in brain function and immune regulation. That too can have downstream effects on mood and cognition. So addressing these things, though, doesn't change the core neurological profile of autism. It really, really can meaningfully improve how a child feels and functions and learns day to day.

So what does testing in this area look like? Well, a basic metabolic and nutritional panel, something that can be ordered by your pediatrician. It can include something like a complete blood count to check for anemia and ferritin, to assess iron levels and iron stores in the body, vitamin D levels, B12, thyroid function, mitochondrial labs, and in some cases even a more detailed metabolic and nutritional panel could be helpful. The third area I want to talk about is brain function, and specifically the role of EEG or electroencephalography.

I want to start by acknowledging that even just the word seizure or epilepsy can feel alarming for parents, and I understand that. So let's take a breath and look at this, step by step. So children with autism have a significantly higher rate of seizures than the general population. The general population, that their rate of epilepsy and the term epilepsy means, recurrent seizures. The rate is roughly 1 to 2% in the general population. But for those with autism, it's somewhere between 15 and 30%.

So around 15 to 30% of autistic individuals will develop epilepsy over their lifetime. And the risk is higher in those who also have intellectual developmental disorder. So why okay. Why is this the case? Well, the honest answer is that we don't fully know yet, but it's likely related to the underlying differences in how neural circuits are organized and connected in autism, the same brain wiring differences that contribute to sensory processing differences, social communication and learning.

Those also affect how neurons synchronize their activity, which is essentially what seizures are. An EEG is a test that measures the electrical activity of the brain using sensors placed on the scalp. It is painless, noninvasive, and can be done while a child is awake or asleep. It can detect patterns of abnormal electrical activity, both the more dramatic kind associated with, visible seizures, but also more subtle patterns that don't produce obvious outward symptoms.

But actually that can still affect learning and behavior. So that second category of the more subtle seizures is worth knowing about because, sometimes parents will notice things like a child who has episodes of maybe zoning out. Like those brief moments where they seem to be maybe not present, less responsive, and then come back and resume as if nothing had happened. Even brief moments of inattention. These can be what are called, absence seizures, a form of epilepsy that can be very easy to miss because they look on the surface like daydreaming or inattention.

And an EEG can distinguish between the two. So which children should have an EEG? Any child who has had developmental progression, which is when a child who has been gaining skills either stops gaining skills or loses them. If there are any episodes that look like they could be seizures, like, involuntary movements. If there are significant sleep disturbances, any sudden or unexplained changes in behavior? And if there are periods of inattention. So if any of those apply to your child, it's absolutely worth raising with your doctor, your pediatrician or your neurologist, that you have some of these concerns like EEG is such an important tool.

Like all tools, it's most useful when it's the right tool for the right situation. EEGs can be done in a clinical setting, in a hospital or at home, and sometimes only 20 minutes of recording is needed. But at other times, several days of recording might be needed. It all depends on the individual child and what they are experiencing. A neurologist can guide you with all of these decisions. Let's talk next about a fascinating and fast moving area of autism science. The gut brain connection. If you have followed autism research at all in the last several years, you've probably seen some version of this story.

So studies showing differences in the gut microbiome in autism. Headlines about probiotics and how they can influence behavior and learning. So I want to first review the solid science. Gastrointestinal symptoms are significantly more common in autism than in neurotypical populations. Research has consistently found that constipation, diarrhea, abdominal pain, reflux, and feeding difficulties affect a large proportion of autistic children.

With some studies putting that figure as high as 50 to 70%, depending on how GI symptoms are defined, and separately, there is a real and well-established biological pathway called the gut brain axis, a bidirectional communication system linking the enteric nervous system in the gut, sometimes also called the second brain, with the central nervous system. This involves the vagus nerve, immune signaling molecules, and neurotransmitters like serotonin. And yes, roughly 90% of the body's serotonin is actually produced in the gut.

Studies have also found differences in the composition of the gut microbiome in autistic individuals compared to neurotypical individuals. Some of these differences are reproducible across studies, meaning they show up consistently enough that researchers take them very seriously. But here's the complicating factor. We know that correlation is not causation. So do microbiome differences contribute to autism features or do they result from the dietary patterns?

Medication use stress patterns that are common in autism? We don't fully know yet. The gut brain connection is real. The research is genuinely exciting, but the clinical application is still evolving. So what's important for you to know now? First, it's very clear that gastrointestinal symptoms and autism are underdiagnosed and undertreated. This matters enormously. Why? Because a child who is in chronic abdominal pain, who is constipated or experiencing acid reflux, may not be able to communicate that pain.

Instead, that discomfort can show up as irritability, aggression, self-injurious behavior, disrupted sleep. Difficulty attending to learning tasks. And when we treat the underlying GI issue, we often see meaningful improvements in all of those things. Behavior, regulation. Learning. And so much more. So when thinking about gut related medical testing and autism, the clinical approach is guided by what the child is experiencing. If your child has constipation, feeding difficulties, reflux, or signs that suggest GI discomfort, those symptoms deserve evaluation and treatment.

Bring them to your doctor. This is not a fringe area. It is basic, important medicine. Now what about tests that look at the makeup of the microbiome itself? Well, there isn't yet consensus around which test is best or when it can be helpful for autism. Some doctors order these tests and others don't. My advice here is to start with the symptom guided approach that I just described, because those are really worthwhile. And then talk with a doctor who you trust, who has expertise in autism and gut health, and decide if there's good rationale to explore new or tests where the research is still emerging.

The fifth area we'll look at is one that has grown substantially in scientific attention over the last decade, and that's the immune system. Here's a framing that I find the most helpful. The immune system and the nervous system are much more deeply connected than we used to realize. They share chemical signals. Immune cells actually patrol the brain. And we know disruptions in immune regulation can have effects on brain development and function. Several lines of research suggest that immune involvement is part of autism, and one of the most studied involves maternal immune activation.

The observation that when a mother experiences certain immune challenges during pregnancy, particularly during certain windows of fetal brain development, that it appears to increase the likelihood of neurodevelopmental differences like autism. It doesn't explain all or even most of autism, but it does suggest that immune brain signaling during development is one piece of an overall more complex picture. There is also research on neuroinflammation. So signs of immune activity in the brain itself, a post postmortem brain studies and some emerging research studies have found evidence of microglial activation.

The brain's resident immune cells, microglia, seem to be chronically activated in some people. This is an area of active research, investigation, and researchers are still trying to understand what it means and whether it's a driver of symptoms or a secondary effect. One more specific finding that's received a lot of attention recently is folate receptor autoantibodies. Now these are antibodies that block the folate receptor in the brain. We know that folate is essential for neurological function.

And when the receptor is blocked, it can impair folate transport into the brain. Even when dietary folate intake is normal. This is a real biological mechanism, and there is research evidence that a specific form of folate supplementation, called leucovorin or folinic acid, can be helpful in this subgroup of people. This area of autism biology, the immune system, and autism is not one where there are broad routine tests to recommend for everyone.

But if your child has certain symptoms like recurring infections, unusual immune related symptoms, like maybe severe types of allergies, or if members of your family have autoimmune conditions, or if your child's doctor has any concerns based on their overall medical history and symptoms. Well, there could be some really important medical tests of your child's immune system that should be done. Okay. We've covered a lot of ground. Let me now give you a practical framework that you can actually use when you're sitting in your doctor's office or deciding what conversations to have next.

Think of it in two layers. Layer one. Start with what's recommended for every child with an autism diagnosis, and that's a chromosomal microarray and fragile X testing. If those tests haven't been done, they should be. This is the foundation beyond genetics, a basic nutritional and metabolic screen is also very reasonable, particularly for children with selective eating or who have signs of low energy. Layer two let your child's symptoms guide the rest. EEG, deeper metabolic and nutritional laboratory testing, targeted immune testing, gastrointestinal tests.

The key is symptom guided, individualized decision making, not a preset checklist applied to every child. And whenever you're weighing a test, whether it's something a doctor is recommending or something you've heard about, something maybe other parents have talked about. I'd encourage you to ask two questions. First, will this test help us understand something meaningful about my child's biology or health? And second, will the result actually change what we do? If the answer to either is yes, it's worth having a serious conversation about it with your care team.

We are living through a transition in autism medicine. For a long time, the approach was largely one size fits all the same evaluations, the same recommendations for every child. But that is changing rapidly. The emerging model is what researchers call precision medicine. The idea that we can integrate genetic, biological, behavioral, environmental information about an individual and create a truly personalized picture of their needs and an individualized approach to their care.

The science is catching up to the complexity of autism, and that is something to feel genuinely hopeful about. Remember, you are not obligated to say yes to every test, and you are not failing your child by being thoughtful and selective. That is, in fact, the most informed approach. Because here's what I want you to hold on to at the end of all of this. Medical testing on its own is not the goal. Understanding your child is the goal. Supporting their biology is the goal. Creating the conditions where they can feel well, learn, connect and grow. That is the goal.

The science is our guide in that work and it's a good guide. It's not perfect, it's not complete, but it is genuinely useful when we know how to read it. Which is exactly what I hope you are walking away with today. Thank you so much for being here for this one. It's a topic that matters, and I'm glad we could spend this time on it together. If this episode was helpful to you, please share it with another parent who might need it. Leave us a review if you have a minute. It truly helps more families find this podcast. And until next time, keep going.

Your curiosity, your advocacy, and your care. They make a world of difference every single day. I'll see you next time on Magnificent Minds.